Well the synth sounds great. I think your a bit to loud against the recording. since the vocals are moved way to the back of the mix. Also your bass playing needs some work. How did you record the bass part? If it was just off of camera audio you need to turn it up a bit so the physical sound of you playing is hidden in the mix a little better. if you were recording it thru a line in or something of the sort just remember to kill the video audio and replace it with a mixed version. also do a little more eq work. Practice the fast bass fill a bit more.